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US4334173A Expired / Lapsed US ⏱️ 0.0 years remaining

Horizontal width control circuit for image display apparatus

Assignee: Zenith Electronics LLC
•
Filing: 1980-09-22
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Granted: 1982-06-08
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Expires: 2000-09-22
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Abstract

Abstract A horizontal width control circuit for use with an image display apparatus includes first and second variable inductors connected in series and shunt relationship respectively with a horizontal deflection coil. The inductance of the inductors are variable in opposite directions for controlling the extent of horizontal deflection through a relatively large range of values without detuning the horizontal deflection circuits.

Inventors

  • 👤 Melvin E. Gabriel
  • 👤 Joseph M. Van Baalen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 17:26
CPC Classifications
H; H04; H04N; H04N3/00; H04N3/10; H04N3/16; H04N3/22; H04N3/223

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 110 words
In an image display apparatus of the type having a horizontal deflection coil responsive to a horizontal deflection circuit for horizontally deflecting an electron beam across the screen of a CRT, a horizontal width control circuit comprising: a first inductor connected in series relationship with said horizontal deflection coil; a second inductor connected in shunt relationship with said horizontal deflection coil; and means manually operable for simultaneously varying the impedance of said first and second inductors in opposite directions to maintain the composite inductance thereof substantially constant, whereby to control the extent to which said electron beam is horizontally deflected across said CRT screen without detuning said horizontal deflection circuit.
Claim 2
Dependent Claim 110 words
In an image display apparatus of the type having a horizontal deflection coil responsive to a horizontal deflection circuit for horizontally deflecting an electron beam across the screen of a CRT, a horizontal width control circuit comprising: a first inductor connected in series relationship with said horizontal deflection coil; a second inductor connected in shunt relationship with said horizontal deflection coil; and means manually operable for simultaneously varying the impedance of said first and second inductors in opposite directions to maintain the composite inductance thereof substantially constant, whereby to control the extent to which said electron beam is horizontally deflected across said CRT screen without detuning said horizontal deflection circuit.
Claim 3
Dependent Claim 42 words
The horizontal width control circuit of claim 1 wherein said first and second inductors are wound in spaced apart relation on a common coil form and wherein said means for varying comprises a single core element longitudinally displaceable within said coil form.
Claim 4
Dependent Claim 137 words
In an image display apparatus of the type having a horizontal deflection coil responsive to a horizontal deflection circuit for horizontally deflecting an electron beam across the screen of a CRT, a horizontal width control circuit comprising: a coil form; a first inductor wound about said coil form and connected in series relationship with said horizontal deflection coil; a second inductor wound about said coil form in spaced relation from said first inductor and connected in shunt relationship with said horizontal deflection coil; and a core element displaceable within said coil form for simultaneously varying the inductance of said first and second inductors in opposite directions to maintain the composite inductance thereof substantially constant, whereby to control the extent to which said electron beam is horizontally deflected across said CRT screen without detuning said horizontal deflection circuit.
Claim 5
Dependent Claim 137 words
In an image display apparatus of the type having a horizontal deflection coil responsive to a horizontal deflection circuit for horizontally deflecting an electron beam across the screen of a CRT, a horizontal width control circuit comprising: a coil form; a first inductor wound about said coil form and connected in series relationship with said horizontal deflection coil; a second inductor wound about said coil form in spaced relation from said first inductor and connected in shunt relationship with said horizontal deflection coil; and a core element displaceable within said coil form for simultaneously varying the inductance of said first and second inductors in opposite directions to maintain the composite inductance thereof substantially constant, whereby to control the extent to which said electron beam is horizontally deflected across said CRT screen without detuning said horizontal deflection circuit.

References Cited (Backward Citations)

US2900565A Cited
US3769542A Cited
DE2305414A1 Cited
US3914650A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-06-07 1985-12-07 1986-06-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-06-07 1989-12-07 1990-06-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-06-07 1993-12-07 1994-06-08 $7700.00 Window Closed / Lapsed

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